Analysis of tool wear and cutting temperature in WS2-assisted MQL turning of H13 steel

This study aims to analyze the turning performance of H13 steel in dry and minimum quantity lubrication (MQL) environments, employing Tungsten Disulfide (WS2) as a solid lubricant. Machining of H13 steel is challenging, particularly in its hardened state. The high hardness and abrasive carbides accelerate tool wear and cutting temperature. The MQL lubricant was prepared by dissolving WS2 nanoparticles into sunflower oil, targeting to enhance both lubrication and cooling efficiency during turning. The primary objective is to evaluate and compare how MQL turning (blend of WS2 nanoparticles and sunflower oil) and dry turning affect cutting temperature and tool wear. Experiments were conducted at varying cutting speeds while keeping feed rate and depth of cut constant to ensure a controlled analysis of the speed influence. A comparative analysis revealed a reduction in flank wear (VBmax) of approximately 12–26% and 7–37% across the tested cutting speed range cutting speeds in MQL environments. Also, the cutting temperature was dropped by 20–25% and 21–27% in MQL environments. Finally, it is evident that WS2 exhibits promising potential as a lubricant and coolant in machining processes. MQL turning with the use WS2 mixed cutting oil with selected parameters can be used in conventional machining industry to improve turning performance of H13 steel.